My inlaws are waiting for us beneath the Gothic porch with mouths unfurling pennants of vapour. Dennis, ex-Squadron Leader, wears a grandiose moustache, tweeds, the pipe he carries a constant reminder of campaign rooms filled with pin-laden maps and old shag, the Battle of Britain, his finest hour. Diana, in plaid skirt and cashmere, kisses me on both cheeks, the consequence of a year at finishing school in Switzerland. Diana is the daughter of a Scottish baronet; Dennis is proud of his wife's pedigree, her imported ways. That good blood had pushed her up an inch more than Miriam could manage, sharpened her hipbones, deepened the blue in her eyes. I have often imagined seducing Diana, a key part of the fantasy being that she is a willing participant. I could bugger Dennis, kill my progeny, turn the humdrum into Oedipal drama.